The invention relates to the method and apparatus for controlling the flow of oxygen and fuel to the burner in an electric arc furnace.
Electric arc furnaces are commonly employed for melting scrap metal which is then further treated in subsequent steel making operations. The heat required for scrap melting is generated by electrical discharges or arcs which pass between the furnace electrodes or between the electrodes and the scrap charge. In order to preheat the furnace and the scrap metal, and to assist in the melting operation, arc furnaces are often provided with oxy-fuel burners. Such burners are shown, for example, in U.S. Pat. Nos. 3,197,539; 3,237,930; 3,459,867; 4,076,617; and 4,156,102. While prior art arc furnaces did achieve some increase in energy efficiency by employing oxy-fuel burners, the burners themselves normally operated at a fuel efficiency range of about sixty percent or less.